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Irreducible Representations of GL_(n)(C)of Minimal Gelfand-Kirillov Dimension

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Acta Mathematica Sinica,English Series 2024年第3期40卷 639-657页

作者： zhan qiang BAI Yang Yang CHEN Dong Wen liu Bin Yong SUN School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China School of Sciences JiangnanUniversityWui214122P.R.China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058P.R.China Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China

In this article,by studying the Bernstein degrees and Goldie rank polynomials,we es-tablish a comparison between the irreducible representations of G=GL_(n)(C)possessing the minimal Gelfand-Kirillov dimension and those induced from finite-dimensional representations of the maximal parabolic subgroup of G of type(n-1,1).We give the transition matrix between the two bases for the corresponding coherent families.

关键词： Bernstein degree coherent continuation Gelfand-Kirillov dimension

The mechanisms of thermal solidification agent promoting steam diversion in heavy oil reservoirs

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Petroleum Science 2024年第3期21卷 1902-1914页

作者： zhan-Xi Pang Qian-Hui Wang qiang Meng Bo Wang Dong liu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Liaohe Oilfield Institute CNPC China Henan Oilfield Institute Sinopec China Tianjin Branch of China National Offshore Oil Company (CNOOC) Ltd.

At high cycles of steam huff & puff, oil distribution in reservoirs becomes stronger heterogeneity due to steam channeling. Thermal solidification agent can be used to solve this problem. Its solution is a lowviscosity liquid at normal temperature, but it can be solidified above 80°C. The plugging degree is up to 99% at 250°C. The sweep efficiency reaches 59.2%, which is 7.3% higher than pure steam injection. In addition, simultaneous injection of viscosity reducer and/or nitrogen foams can further enhance oil recovery. The mechanism of this technology depends on its strong plugging ability, which changes the flowing pattern of steam to effectively mobilize remaining oil. Viscosity reducer and nitrogen foams further expand the sweep range and extends the effective period. Therefore, thermal solidification agent can plug steam channeling paths and adjust steam flowing direction to significantly enhance oil recovery at high cycles of steam huff & puff.

关键词： Heavy oil reservoir Steam huff & puff Steam channeling Steam diversion Plugging performance Mechanism analysis

Prediction of temperature field in machined workpiece surface during the cutting of Inconel 718 coated with surface-active media

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Advances in Manufacturing 2023年第3期11卷 378-389页

作者： Qing-An Yin zhan-qiang liu Bing Wang School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key National Demonstration Center for Experimental Mechanical Engineering Education/Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MQE Jinan 250061People's Republic of China

The heat generated and accumulated on the machined surface of an Inconel 718 workpiece causes thermal damage during the cutting process.Surface-active media with high thermal conductivity coated on the workpiece to be machined may have the potential to reduce the generation of cutting heat.In this study,a theoretical model for predicting the instantaneous machined surface temperature field is proposed for surface-active thermal conductive medium(SACM)-assisted cutting based on the finite element and Fourier heat transfer theories.Orthogonal cutting experiments were performed to verify the results predicted using the proposed surface-temperature field model.Three SACMs with various thermal conductivities were used to coat Inconel 718 surface to be machined.Thermocouples embedded into the workpiece were used to measure the cutting temperature at different points on the machined workpiece surface during the cutting process.The experimental results were in agreement with the predicted temperatures,and the maximum error between the experimental results and predicted temperatures was approximately 9.5%.The cutting temperature on the machined surface decreased with an increase in the thermal conductivity of the SACM.The graphene SACM with high thermal conductivity can effectively reduce the temperature from 542℃ to 402℃,which corresponds to a reduction of approximately 26%.The temperature reduction due to SACM decreases with an increase in the distance between the temperature prediction point and machined workpiece surface.In conclusion,the cutting temperatures on the machined workpiece surface can be reduced by coating with SACM.

关键词： Surface-active thermal conductive media(SACM) Finite element model Cutting heat Cutting temperature Inconel 718

Molecular phylogenetic relationships based on mitochondrial genomes of novel deep-sea corals(Octocorallia:Alcyonacea):Insights into slow evolution and adaptation to extreme deep-sea environments

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Zoological Research 2024年第1期45卷 215-225页

作者： zhan-Fei Wei Kai-Wen Ta Nan-Nan zhang Shan-Shan liu Liang Meng Kai-qiang liu Chong-Yang Cai Xiao-Tong Peng Chang-Wei Shao National Key Laboratory of Mariculture Biobreeding and Sustainable Goods Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdaoShandong 266071China BGI-Qingdao BGI-ShenzhenQingdaoShandong 266555China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanyaHainan 572000China

A total of 10 specimens of Alcyonacea corals were collected at depths ranging from 905 m to 1633 m by the manned submersible Shenhai Yongshi during two cruises in the South China Sea(SCS).Based on mitochondrial genomic characteristics,morphological examination,and sclerite scanning electron microscopy,the samples were categorized into four suborders(Calcaxonia,Holaxonia,Scleraxonia,and Stolonifera),and identified as 9 possible new cold-water coral species.Assessments of GC-skew dissimilarity,phylogenetic distance,and average nucleotide identity(ANI)revealed a slow evolutionary rate for the octocoral mitochondrial sequences.The nonsynonymous(Ka)to synonymous(Ks)substitution ratio(Ka/Ks)suggested that the 14 protein-coding genes(PCGs)were under purifying selection,likely due to specific deep-sea environmental pressures.Correlation analysis of the median Ka/Ks values of five gene families and environmental factors indicated that the genes encoding cytochrome b(cyt b)and DNA mismatch repair protein(mutS)may be influenced by environmental factors in the context of deep-sea species formation.This study highlights the slow evolutionary pace and adaptive mechanisms of deep-sea corals.

关键词： Mitochondrial genome Alcyonacea Ka/Ks evolution Environmental factors

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： qiang-qiang liu Shu-Ting liu Ying-Guang Li Xu liu Xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite parts.Traditional embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the part.In this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is proposed.Using the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating patterns.In addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the part.This method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Spontaneous Infection and Periodic Evolving of Domain in a Diffusive SIS Epidemic Model

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 164-191页

作者： qiang Wen Guo-qiang Ren Bin liu School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan430074China

In this paper, we consider a susceptible-infective-susceptible(SIS) reaction-diffusion epidemic model with spontaneous infection and logistic source in a periodically evolving domain. Using the iterative technique,the uniform boundedness of solution is established. In addition, the spatial-temporal risk index R0(ρ) depending on the domain evolution rate ρ(t) as well as its analytical properties are discussed. The monotonicity of R0(ρ)with respect to the diffusion coefficients of the infected dI, the spontaneous infection rate η(ρ(t)y) and interval length L is investigated under appropriate conditions. Further, the existence and asymptotic behavior of periodic endemic equilibria are explored by upper and lower solution method. Finally, some numerical simulations are presented to illustrate our analytical results. Our results provide valuable information for disease control and prevention.

关键词： diffusive SIS model spontaneous infection periodically evolving domain periodic endemic equilibrium

Singlet oxygen-dominated peroxymonosulfate activation by layered crednerite for organic pollutants degradation in high salinity wastewater

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Journal of Environmental Sciences 2024年第1期135卷 86-96页

作者： Chengji Sui Zixuan Nie Huan liu Grzegorz Boczkaj Weizhen liu Lingshuai Kong Jinhua zhan Key Laboratory for Colloid&Interface Chemistry of Education Ministry Department of ChemistryShandong UniversityJinan 250100China School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and RecyclingSouth China University of TechnologyGuangzhou 510006China Gdansk University of Technology Faculty of Civil and Environmental EngineeringDepartment of Sanitary EngineeringG.Narutowicza St.11/1280-233 GdanskPoland EkoTech Center Gdansk University of TechnologyG.Narutowicza St.11/1280-233 GdanskPoland

Advanced oxidation processes have been widely studied for organic pollutants treatment in water,but the degradation performance of radical-dominated pathway was severely inhibited by the side reactions between the anions and radicals,especially in high salinity conditions.Here,a singlet oxygen(^(1)O_(2))-dominated non-radical process was developed for organic pollutants degradation in high salinity wastewater,with layered crednerite(CuMnO_(2))as catalysts and peroxymonosulfate(PMS)as oxidant.Based on the experiments and density functional theory calculations,^(1)O_(2)was the dominating reactive species and the constructed Cu-O-Mn with electron-deficient Mn captured electron from PMS promoting the generation of^(1)O_(2).The rapid degradation of bisphenol A(BPA)was achieved by CuMnO_(2)/PMS system,which was 5-fold and 21-fold higher than that in Mn_(2)O_(3)/PMS system and Cu_(2)O/PMS system.The CuMnO_(2)/PMS system shown prominent BPA removal performance under high salinity conditions,prominent PMS utilization efficiency,outstanding total organic carbon removal rate,wide range of applicable pH and good stability.This work unveiled that the^(1)O_(2)-dominated non-radical process of CuMnO_(2)/PMS system overcame the inhibitory effect of anions in high salinity conditions,which provided a promising technique to remove organic pollutants from high saline wastewater.

关键词： Singlet oxygen Non-radical process High salinity Mixed metal oxides Wastewater treatment

Skull and vertebral bone marrow in central nervous system inflammation

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Fundamental Research 2024年第2期4卷 246-250页

作者： Honglei Ren qiang liu Department of Neurology Tianjin Neurological InstituteTianjin Institute of ImmunologyState Key Laboratory of Experimental HematologyInternational Joint Laboratory of Ocular DiseasesMinistry of EducationHaihe Laboratory of Cell EcosystemTianjin Medical University General HospitalTianjin 300052China

Emerging evidence has highlighted the capacity of hematogenous cells in skull and vertebral bone marrow to enter the meningeal borders via ossified vascular channels and maintain immune homeostasis in the central nervous system(CNS).CNS-adjacent skull and vertebral bone marrow comprises hematopoietic niches that can sense CNS injury and supply specialized immune cells to fine-tune inflammatory responses.Here,we review recent advances in our understanding of skull and vertebral bone marrow-derived immune cells in homeostasis and inflammatory CNS diseases.Further,we discuss the implications for future development of therapies to mitigate CNS inflammation and its detrimental sequelae in neurological disorders.

关键词： Central nervous system Bone marrow Hematopoiesis Immune cells Neuroinflammation Stroke Multiple sclerosis

Thymoquinone affects hypoxia-inducible factor-1αexpression in pancreatic cancer cells via HSP90 and PI3K/AKT/mTOR pathways

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World Journal of Gastroenterology 2024年第21期30卷 2793-2816页

作者： zhan-Xue Zhao Shuai Li Lin-Xun liu Department of General Surgery Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina Department of Clinical Pharmacy The Affiliated Hospital of Qinghai UniversityXining 810001Qinghai ProvinceChina

BACKGROUND Pancreatic cancer(PC)is associated with some of the worst prognoses of all major cancers.Thymoquinone(TQ)has a long history in traditional medical practice and is known for its anti-cancer,anti-inflammatory,anti-fibrosis and antioxidant pharmacological activities.Recent studies on hypoxia-inducible factor-1α(HIF-1α)and PC have shown that HIF-1αaffects the occurrence and development of PC in many aspects.In addition,TQ could inhibit the development of renal cancer by decreasing the expression of HIF-1α.Therefore,we speculate whether TQ affects HIF-1αexpression in PC cells and explore the mechanism.AIM To elucidate the effect of TQ in PC cells and the regulatory mechanism of HIF-1αexpression.METHODS Cell counting kit-8 assay,Transwell assay and flow cytometry were performed to detect the effects of TQ on the proliferative activity,migration and invasion ability and apoptosis of PANC-1 cells and normal pancreatic duct epithelial(hTERTHPNE)cells.Quantitative real-time polymerase chain reaction and western blot assay were performed to detect the expression of HIF-1αmRNA and protein in PC cells.The effects of TQ on the HIF-1αprotein initial expression pathway and ubiquitination degradation in PANC-1 cells were examined by western blot assay and co-immunoprecipitation.RESULTS TQ significantly inhibited proliferative activity,migration,and invasion ability and promoted apoptosis of PANC-1 cells;however,no significant effects on hTERT-HPNE cells were observed.TQ significantly reduced the mRNA and protein expression levels of HIF-1αin PANC-1,AsPC-1,and BxPC-3 cells.TQ significantly inhibited the expression of the HIF-1αinitial expression pathway(PI3K/AKT/mTOR)related proteins,and promoted the ubiquitination degradation of the HIF-1αprotein in PANC-1 cells.TQ had no effect on the hydroxylation and von Hippel Lindau protein mediated ubiquitination degradation of the HIF-1αprotein but affected the stability of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90,thus promoting its ubiquitination

关键词： Thymoquinone Pancreatic cancer Hypoxia-inducible factor-1α PI3K/AKT/mTOR HSP90